Let's get one thing straight: We do not hate green cars. We like green cars. We like diesel. We like weirdness and engineering genius. Which is why we decided to conduct a fuel-economy experiment with a heavy right foot.

In the wake of the diesel tide that was the Detroit Auto Show, we decided to hoodwink talk our friends at Honeywell into providing us with some of the most forbidden fruits of the Euro-spec diesel world. As a result we've been living and commuting with the not-for-the-USA 2007 Honda Civic i-CTDi and the 2007 Audi Q7…